Bone Shield with Blood Shield
Don't forget though, you're also not taking a bunch of damage from the mobs in ZG. When you actually do things that are equivalent to your level I think its unrealistic to think that at level 85 you'll see less of the whole 'double dipping' functionality between the two.Between the two abilities strictly, yes it's quite likely that there won't be as much of them working in tandem.
However the 20% from Bone Shield is also going to help Anti-Magic Shell, Power Word: Shield, PW: Barrier until it's upcoming change, Divine Aegis, Illuminated Healing, and any other absorbs that may come up in addition to Blood Shield. If you're in a raid with plenty of sources for these effects, Bone Shield could conceivably last far longer than what we're used to.
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